This project is designed to explore the feasibility of using somatic cells to screen for chemically induced chromosomal aberrations. The use of somatic cells for screening purposes would allow for rapid screening of large numbers of animals provided such techniques are reliable in the detection of aberrations. Included in this project are comparisons with respect to the efficiency of detection of chromosome aberrations in germ cells (testicular preparations and sperm morphology), cultured lymphocytes and bone marrow preparations.